Добавлен ~/config-reader

config-reader/index.ts

+import * as t from '../decoder';
+import { camelCase } from 'lodash';
+import { absurd } from '../types';
+
+
+/** 
+ * Источник данных для чтения конфигов
+ */
+export type ConfigSource =
+  | { tag: 'Cli', args: string[], prefix: string }
+  | { tag: 'Location/search', value: string, transformKey(x: string): string }
+  | { tag: 'JSON', value: object }
+  | { tag: 'Concat', sources: ConfigSource[] }
+
+
+export function cli(args: string[], prefix: string = ''): ConfigSource {
+  return { tag: 'Cli', args, prefix };
+}
+
+
+export function queryString(value: string, transformKey = camelCase): ConfigSource {
+  return { tag: 'Location/search', value, transformKey };
+}
+
+
+export function json(value: object): ConfigSource {
+  return { tag: 'JSON', value };
+}
+
+
+export function concat(...sources: ConfigSource[]): ConfigSource {
+  return { tag: 'Concat', sources };
+}
+
+
+export function validate<A>(config: ConfigSource, decoder: t.RecordDecoder<A>) {
+  return decoder.validate(merge(decoder, config));
+}
+
+
+export function merge<A>(decoder: t.RecordDecoder<A>, ...srcs: ConfigSource[]): object {
+  const source = srcs.length === 1 ? srcs[0] : concat(...srcs);
+  if (source.tag === 'Cli') {
+    const value: Record<string, any> = {};
+    for (let i = 0; i < source.args.length; i++) {
+      const prefixLen = '--'.length + source.prefix.length;
+      const rest = source.args[i].substr(prefixLen);
+      const [k, v] = rest.indexOf('=') === -1 ? [rest, source.args[++i] || ''] : source.args[i].split('=');
+      // Проверка того что это известно
+      if (!decoder.description.hasOwnProperty(k)) continue;
+      value[k] = decoderFromString(decoder.description[k], v);
+    }
+    return value;    
+  }
+
+  if (source.tag === 'Location/search') {
+    const substring = source.value[0] === '?' ? source.value.substr(1) : source.value;
+    const value = substring.split('&').map(x => x.split('=')).reduce((acc, [k, v]: any) => {
+      const key = source.transformKey(decodeURIComponent(k));
+      if (!decoder.description.hasOwnProperty(key)) return acc;
+      acc[key] = decoderFromString(decoder.description[key], decodeURIComponent(v));
+      return acc;
+    }, {});
+    return value;
+  }
+
+  if (source.tag === 'JSON') {
+    return source.value;
+  }
+
+  if (source.tag === 'Concat' ) {
+    // @ts-ignore
+    return Object.assign({}, ...source.sources.map(x => merge(decoder, x)));
+  }
+  
+  return absurd(source);
+}
+
+
+export function decoderFromString(decoder: t.Decoder<any>, value: string): any {
+  if (decoder instanceof t.CustomDecoder) {
+    throw new Error('[config-reader] CustomDecoder is not supported');
+  }
+
+  if (decoder instanceof t.ArrayDecoder) {
+    return value.split(', ').map(x => decoderFromString(decoder.decoder, x));
+  }
+
+  if (decoder instanceof t.DictionaryDecoder) {
+    try {
+      return JSON.parse(value);
+    } catch(e) {
+      return value;
+    }
+  }
+  
+  if (decoder instanceof t.RecordDecoder) {
+    try {
+      return JSON.parse(value);
+    } catch(e) {
+      return value;
+    }
+  }
+  
+  if (decoder instanceof t.AtDecoder) {
+    try {
+      return JSON.parse(value);
+    } catch(e) {
+      return value;
+    }
+  }
+
+  if (decoder instanceof t.PrimitiveDecoder) {
+    if (decoder.primitive === 'string') return value;
+    if (decoder.primitive === 'boolean') return !(value === 'false' || value === '0');
+    if (decoder.primitive === 'undefined') return undefined;
+    if (decoder.primitive === 'null') return null;
+    if (decoder.primitive === 'any') return value;
+    if (decoder.primitive === 'nat') return Number(value);
+    if (decoder.primitive === 'int') return Number(value);
+    if (decoder.primitive === 'float') return Number(value);
+    return absurd(decoder.primitive);
+  }
+  
+  if (decoder instanceof t.PureDecoder) {
+    return value;
+  }
+  
+  if (decoder instanceof t.ChainDecoder) {
+    throw new Error('[config-reader] ChainDecoder is not supported');
+  }
+  
+  if (decoder instanceof t.OneOfDecoder) {
+    throw new Error('[config-reader] OneOfDecoder is not supported');
+  }
+  
+  if (decoder instanceof t.DiscriminatedDecoder) {
+    try {
+      return JSON.parse(value);
+    } catch(e) {
+      return value;
+    }
+  }
+
+  if (decoder instanceof t.HasDecoder) {
+    if (decoder instanceof t.WithDefaultDecoder) {
+      return decoderFromString(decoder.decoder, value);
+    }
+    
+    return decoderFromString(decoder.toDecoder(), value);
+  }
+
+  return absurd(decoder);
+}

decoder/index.ts

@@ -49,7 +49,7 @@ const defaultValidateOptions: ValidateOptions = {
 // Базовый класс для наследования методов
 export class DecoderBase<A> {
   readonly _A: A;
-  static rootDecoder: Decoder<any>;
+  static rootDecoder: Decoder<any>|undefined = undefined;
   static rootValue: any = undefined;
 
   /**
@@ -120,7 +120,7 @@ export class DecoderBase<A> {
   withDefault(defValue: A): Decoder<A>;
   withDefault<B extends Expr>(defValue: B): Decoder<A|B>;
   withDefault<B extends Expr>(defValue: B): Decoder<A|B> {
-    return new OneOfDecoder([this as any, of(defValue)]);
+    return new WithDefaultDecoder(this as any, defValue);
   }
 
   refine(pred: (a: A) => boolean): Decoder<A> {
@@ -254,19 +254,23 @@ export class DiscriminatedDecoder<A> extends DecoderBase<A> {
 /** 
  * `discriminateOn` комбинатор
  */
-export class WithDefaultDecoder<A> extends DecoderBase<A> {
-  constructor(
-    readonly decoder: Decoder<A>,
-    readonly defaultValue: A,
-  ) { super(); }
+export abstract class HasDecoder<A> extends DecoderBase<A> {
+  abstract toDecoder(): Decoder<A>;
 }
 
 
 /** 
  * `discriminateOn` комбинатор
  */
-export abstract class HasDecoder<A> extends DecoderBase<A> {
-  abstract toDecoder(): Decoder<A>;
+export class WithDefaultDecoder<A> extends HasDecoder<A> {
+  constructor(
+    readonly decoder: Decoder<A>,
+    readonly defaultValue: A,
+  ) { super(); }
+
+  toDecoder() {
+    return new OneOfDecoder<A>([this.decoder, of(this.defaultValue)]);
+  }
 }
 
 
@@ -495,17 +499,6 @@ function fancyTypeOf(value: any): string {
 }
 
 
-// Хелпер
-function prettyPrintPath(path: Array<string|number>): string {
-  let output = '_';
-  for (let i = path.length - 1; i >= 0; i--) {
-    if (/^[a-zA-Z_$][\w_$]*$/.test('' + path[i])) output += '.' + path[i];
-    else output += `[${JSON.stringify(path[i])}]`;
-  }
-  return output;
-}
-
-
 /**
  * Выполнение валидации
  */
@@ -518,9 +511,9 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
     const output: any[] = [];
     if (!Array.isArray(value)) return Either.failure(projectProblem('not an array'));
     for (let i = 0; i < value.length; i++) {
-      const ethr = this.decoder.validate(value[i]);
+      const ethr = doValidate(decoder.decoder, value[i]);
       switch(ethr.tag) {
-        case 'Left': { ethr.value.path.push(i); return ethr; }
+        case 'Left': { return ethr; }
         case 'Right': output.push(ethr.value); break;
       }
     }
@@ -528,14 +521,14 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
   }
 
   if (decoder instanceof DictionaryDecoder) {
-    if (value === null) return Either.failure(projectProblem('found null'));
     if (typeof (value) !== 'object') return Either.failure(projectProblem('not an object'));
+    if (value === null) return Either.failure(projectProblem('found null'));
     const output: { [k: string]: A } = {};
     for (let key in value) {
       if (!value.hasOwnProperty(key)) continue;
-      const ethr = this.decoder.validate(value[key]);
+      const ethr = doValidate(decoder.decoder, value[key]);
       switch(ethr.tag) {
-        case 'Left': { ethr.value.path.push(key); return ethr; }
+        case 'Left': { return ethr; }
         case 'Right': output[key] = ethr.value; break;
       }
     }
@@ -543,14 +536,14 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
   }
 
   if (decoder instanceof RecordDecoder) {
-    if (value === null) return Either.failure(projectProblem('found null'));
     if (typeof (value) !== 'object') return Either.failure(projectProblem('not an object'));
+    if (value === null) return Either.failure(projectProblem('found null'));
     const output: { [k: string]: any } = {};
-    for (let key in this.description) {
-      if (!this.description.hasOwnProperty(key)) continue;
-      const ethr = this.description[key].validate(value[key]);
+    for (let key in decoder.description) {
+      if (!decoder.description.hasOwnProperty(key)) continue;
+      const ethr = doValidate(decoder.description[key], value[key]);
       switch(ethr.tag) {
-        case 'Left': { ethr.value.path.push(key); return ethr; }
+        case 'Left': { return ethr; }
         case 'Right': output[key] = ethr.value; break;
       }
     }
@@ -559,14 +552,14 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
 
   if (decoder instanceof AtDecoder) {
     let iter = value as any;
-    for (let i in this.path) {
-      if (iter === undefined || !iter.hasOwnProperty(this.path[i])) {
+    for (let i in decoder.path) {
+      if (iter === undefined || !iter.hasOwnProperty(decoder.path[i])) {
         iter = undefined;
         break;
       }
-      iter = iter[this.path[i]];
+      iter = iter[decoder.path[i]];
     }
-    return this.decoder.validate(iter);
+    return doValidate(decoder.decoder, iter);
   }
  
   if (decoder instanceof PrimitiveDecoder) {
@@ -588,8 +581,8 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
   }
   
   if (decoder instanceof OneOfDecoder) {
-    for (const decoder of this.alternatives) {
-      const ethr = decoder.validate(value);
+    for (const d of decoder.alternatives) {
+      const ethr = doValidate(d, value);
       switch(ethr.tag) {
         case 'Left': break;
         case 'Right': return ethr;
@@ -619,7 +612,7 @@ export function doValidate<A>(decoder: Decoder<A>, value: unknown): Either<Probl
 
   function projectProblem(problem: Problem|string): Problem {
     if (typeof(problem) !== 'string') return problem;
-    return { value, rootValue: DecoderBase.rootValue, decoder, rootDecoder: DecoderBase.rootDecoder, message: problem, };
+    return { value, rootValue: DecoderBase.rootValue, decoder, rootDecoder: DecoderBase.rootDecoder || decoder, message: problem, };
   }  
 }